42 lines
673 B
Go
42 lines
673 B
Go
// +build darwin dragonfly freebsd linux netbsd openbsd
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package flock
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import (
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"os"
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"syscall"
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)
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type unixLock struct {
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f *os.File
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}
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func (l *unixLock) Release() error {
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if err := l.set(false); err != nil {
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return err
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}
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return l.f.Close()
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}
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func (l *unixLock) set(lock bool) error {
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how := syscall.LOCK_UN
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if lock {
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how = syscall.LOCK_EX
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}
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return syscall.Flock(int(l.f.Fd()), how|syscall.LOCK_NB)
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}
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func newLock(fileName string) (Releaser, error) {
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f, err := os.OpenFile(fileName, os.O_RDWR|os.O_CREATE, 0644)
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if err != nil {
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return nil, err
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}
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l := &unixLock{f}
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err = l.set(true)
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if err != nil {
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f.Close()
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return nil, err
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}
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return l, nil
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}
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